Tatami IBJJF Short Sleeve Rank Rash Guard

New Tatami Fightwear short sleeve IBJJF rank rash guards made from ultra high quality polyspandex material. These rash guards feature a striking new design that complies with the IBJJF NO GI unifrom requirements.

This rush guard is listed under standard sizing chart (Small, instead of A -gi men's size-). In men's shirt size chest measurement for size small is 36". Women's size small has chest measurement of 35". It's quite close. But as you stated being size F1 which means you must be under 100 lb and a petite lady, which in regular sizing would be XS. So, this shirt would be a little bit big for you.